By the generic expression automatic gearbox is to be understood electrohydraulically controlled automatic gearboxs where the gearshift is carried out as cross-over gearshift. In cross-over gearshifts, the gearshift results by a first clutch or brake releasing and second clutch or brake engaging. In automatic gearboxs, it is usual, in general, to monitor the orderly operation thereof in order to prevent situations critical to safety. Monitored are the input signals made available by the sensors, the electromagnetic actuators, the electronic transmission control and, via acknowledged variables, the clutches and brakes that take part in the gearshift. It is of special interest here to detect a faulty releasing of a clutch or brake since this can result in the blocking of the transmission and subsequent destruction. A faulty release is thus extremely critical to safety.